Brett grew up in Newark, New Jersey. She attended Barnard College and received her BA in 1897 and completed her MA at Columbia University in 1900. From 1900 Brett spent two years as a Fellow at the American School of Classical Studies at Athens. While in Athens, Brett worked on the coin finds from the American School of Classical Studies at Athens excavation at Corinth and published them in 1903. In 1910 Brett became the first female curator at the American Numismatic Society and remained closely connected with the institution until her death. She became an honorary Associate Curator of Ancient Coins from 1923 to 1955 and she also served as chair of the ANS Publications Committee from 1923 to 1946. Brett's correspondence and manuscripts are now housed in the American Numismatic Society's archives.
Brett was awarded the Medal of the Royal Numismatic Society in 1943. She was unable to attend the meeting to receive her medal and the Proceedings of the Royal Numismatic Society for 1943 describe how John Allan received the award on Brett's behalf and read an acceptance letter. The President of the Royal Numismatic Society, Harold Mattingly, noted that Brett was the second American, and the second female to receive the Medal. Mattingly concluded his speech by noting
Brett was the second recipient of the ANS Huntington Medal in 1919.
Collections
Brett collected Babylonian Cylinder seals and her collection was published in 1936 by the University of Chicago Oriental Institute. There is a collection of photographs taken by Agnes Baldwin Brett at the American Numismatic Society from her travels between 1900 and 1909 through Bermuda, Greece, France, Italy, Turkey, and Great Britain. The photo archive was digitised and made available online by the American Numismatic Society in 2017.
Family
Agnes Baldwin married George Monroe Brett in 1914 and had one daughter, Barbara Brett Sanders.
Publications
Books
Five Roman Gold Medallions, or, Multiple Solidi of the Late Empire, The American Numismatic Society: Numismatic Notes and Monographs, no. 6
Six Roman Bronze Medallions, The American Numismatic Society: Numismatic Notes and Monographs, no. 17
Four medallions from the Arras hoard, The American Numismatic Society: Numismatic Notes and Monographs, no. 28
Victory issues of Syracuse after 413 B.C., The American Numismatic Society: Numismatic Notes and Monographs, no. 75
"A bronze coin of Bithynia: The Lyre, Chelys", in Journal International d'Archeologie Numismatique 4 67-76
"The gold coinage of Lampsacus", in Journal International d'Archeologie Numismatique 5 5-24
"The cave at Vari. V. coins", in American Journal of Archaeology 7 335-337
"Facing heads on ancient Greek coins", in American Journal of Numismatics 43 no. 3 113-131
"M. Godefroid Devreese", in American Journal of Numismatics 44, no. 2 61-63
"The Virginia half-pennies", in The Numismatist 24, no. 8 276
"Les monnaies de bronze dites incertaines du Pont ou du Royaume de Mithridate Eupator", in Revue Numismatique 4th ser., 17 285-313
"The electrum and silver coins of Chios, issued during the sixth, fifth, and fourth centuries, B.C.: A chronological study", in American Journal of Numismatics 48 1-60
"Symbolism on Greek coins", in American Journal of Numismatics 49 89-194
"An unedited gold stater of Lampsakos", in Zeitschrift für Numismatik 32 1-14
"The double sestertius of Trajan Decius", in The Numismatist 33, no. 6 277-279
"A Roman gold bar from Egypt", in The Numismatist 33, no. 6 279-281
"Lampsakos; the gold staters, silver and bronze coinages", in American Journal of Numismatics 53, pt. 3: 1-77
"Un tresor monetaire decouvert a Cesaree en Cappadoce", in Arethuse 4 145-172
"Tetradrachms of Demetrius Poliorcertes", in Bulletin of the Museum of Fine Arts 28, no. 168 71-72
"Tetradrachm of Maussolus", in Bulletin of the Museum of Fine Arts 29, no. 171 11-13
"The aurei and solidi of the Arras hoard", in The Numismatic Chronicle 5th ser., 13 268-348
"The Aphlaston, symbol of naval victory or supremacy on Greek and Roman coins", in Transactions of the International Numismatic Congress Ed. J. Allan, H. Mattingly, and E.S.G. Robinson 23-32
"A new Cleopatra tetradrachm of Ascalon", in American Journal of Archaeology 34, no. 3 452-463
"Philip of Macedon's race horse, winner at the Olympic Games, 356 B.C.", in Numismatic Review 1, no. 1 5-6
"Seleucid coins of Ake-Ptolemais in Phoenicia", in ANS Museum Notes 1 17-35
"Dated coins of Ptolemy V, 204-180 B.C.", in ANS Museum Notes 2 1-11
"Indo-Bactrian coins acquired by the American Numismatic Society in 1947", in ANS Museum Notes 3 31-43
"The mint of Ascalon under the Seleucids", in ANS Museum Notes 4 43-54
"Athena Alkidemos of Pella", in ANS Museum Notes 4 55-72
"The Benha hoard of Ptolemaic gold coins", in ANS Museum Notes 5 1-8
